import numpy as np
theta = 2*np.pi*np.arange(200)/20
x1 = np.sin(theta).reshape((1,200))
print(x1.shape)
verticalstripes = np.repeat(x1, repeats=200, axis=0)
import matplotlib.pyplot as plt
plt.imshow(1+verticalstripes)
plt.title('Vertical Stripes with a frequency of $\omega_2=0.1\pi$')
(1, 200)
Text(0.5, 1.0, 'Vertical Stripes with a frequency of $\\omega_2=0.1\\pi$')